This invention relates to templates designed specifically for marking cut lines for construction of roof rafters. In particular, the invention provides a single template which may be used to facilitate all rafter cuts necessary to be made in the construction of a sloping roof.
In the construction of a typical sloping roof, a number of specific cuts must be made in various sizes of boards in order to construct the frame of the roof. The types of cuts which need to be made will depend upon the height and width of the building, the pitch of the roof, and the dimensions of the various structural elements such as the ridgeboard, plates, and rafters. In general, a horizontal ridgeboard is positioned centrally at the upper portion of the roof, and is supported by various elevated boards or rafters above a horizontal "top plate" which extends around the periphery of the roof. The top plates are generally supported by vertical studs which extend upwardly from a bottom plate. Depending on the roof design, the cutting of rectangular boards to fit properly at all locations on the roof is an art which may require many complex cuts at various oblique angles on the wood. In order for the roof to be constructed properly, it is essential that the various components have surfaces which meet in a flush manner.
The laying out of roof truss members is often a time consuming job requiring error-free computations and measurements, and frequently involves trial and error fittings which must be done more than once. The present invention provides a template which can be used as a guide to draw cut lines along various truss members, and eliminates trial and error on all truss cuts. Accordingly, the object of the present invention is to provide a template or guide which may be used to define accurate cutting surfaces for roof trusses. It is a further object of the invention to minimize the number of calculations necessary to determine the proper angle of cuts for such members. It is yet a further object of the invention to provide a single template which may be used for substantially all rafter cuts. These and other objects are accomplished by the use of the tool of the invention, a detailed description of which is contained herein.
Other carpenter's templates have been used for the purpose of assisting in laying out of roof trusses. Doner, U.S. Pat. No. 1,125,010 discloses a simple tool having various guide slots for common rafters and jack rafters. Haley, U.S. Pat. No. 2,965,969 shows a similar tool having a single slot and a triangular cut-out for marking a heel cut in a rafter. This tool is also used for making ridge cuts and tail cuts. Shaw, U.S. Pat. No. 3,183,596, and McKinley, U.S. Pat. No. 3,010,209 disclose various templates for rafter marking which are used in sets depending upon the particular angles necessary.